共查询到20条相似文献,搜索用时 15 毫秒
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Atsushi Kawachi Takuya Teranishi Takuma Deguchi Yohsuke Yamamoto 《Heteroatom Chemistry》2013,24(1):53-57
The countercation effect on the reactivity of ambiphilic o‐(fluorodimethylsilyl)phenyl anion was investigated by replacing Li in 1 with Cu ( 4 and 5 ), Mg ( 6 ), and Zn ( 7 ). The reactivity of the aryl metal species was estimated by the yields of dimerized product 3 , which were monitored by GC. X‐ray crystallographic analysis, DFT calculations, and AIM analysis of bis(aryl)zinc 7 were performed. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:53–57, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21062 相似文献
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四(4-硝基苯基)卟啉和四(4-氨基苯基)卟啉的合成 总被引:20,自引:1,他引:20
四(4氨基苯基)卟啉(TAPP)是含有4个反应活性基团的卟啉衍生物,可在模拟某些生物过程或氧化还原反应的树枝状或簇状分子中作为富电子中心,也可直接用来制备光电器件或作为光电功能聚合物的功能单体和交联剂,因此,TAPP的合成研究具有重要意义[1].... 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(27):8211-8215
The reaction of [(Cp*Mo)2(μ‐Cl)2B2H6] ( 1 ) with CO at room temperature led to the formation of the highly fluxional species [{Cp*Mo(CO)2}2{μ‐η2:η2‐B2H4}] ( 2 ). Compound 2, to the best of our knowledge, is the first example of a bimetallic diborane(4) conforming to a singly bridged Cs structure. Theoretical studies show that 2 mimics the Cotton dimolybdenum–alkyne complex [{CpMo(CO)2}2C2H2]. In an attempt to replace two hydrogen atoms of diborane(4) in 2 with a 2e [W(CO)4] fragment, [{Cp*Mo(CO)2}2 B2H2W(CO)4] ( 3 ) was isolated upon treatment with [W(CO)5⋅thf]. Compound 3 shows the intriguing presence of [B2H2] with a short B−B length of 1.624(4) Å. We isolated the tungsten analogues of 3 , [{Cp*W(CO)2}2B2H2W(CO)4] ( 4 ) and [{Cp*W(CO)2}2B2H2Mo(CO)4] ( 5 ), which provided direct proof of the existence of the tungsten analogue of 2 . 相似文献
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Motohiro Aiba Xiao‐Cheng Sun Yuji Shibasaki Mitsuo Oda Chihiro Ooka Seijiro Fukuta Tomoya Higashihara Shinji Ando Mitsuru Ueda Wen‐Chang Chen 《Journal of polymer science. Part A, Polymer chemistry》2019,57(8):878-884
The oxidative coupling polymerization of o‐cresol was investigated using various 2‐substituted pyridine/CuCl catalysts under an oxygen atmosphere, in which 2‐phenylpyridine/CuCl and 2‐(p‐tolyl)pyridine/CuCl catalysts yielded poly(o‐cresol)s with higher regioselectivity for 1,4‐coupling. These polymerizations produced branched and crosslinked polymers in the later stages of polymerization. These polymers showed good thermal properties, such as 5% weight loss temperatures of up to 406 °C and glass transition temperatures of up to 151 °C. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 878–884 相似文献
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A new series of 2,3‐disubstituted quinazolin‐4(3H)‐one derivatives was synthesized by nucleophilic attack at C(2) of the corresponding key starting material 2‐propyl‐4H‐3,1‐benzoxazin‐4‐one (Scheme 2). The reaction proceeded via amidinium salt formation (Scheme 3) rather than via an N‐acylanthranilimide. The structure of the prepared compounds were elucidated by physical and spectral data like FT‐IR, 1H‐NMR, and mass spectroscopy. 相似文献
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Hongying Zhuo Hong Yu Qingzhong Li Wenzuo Li Jianbo Cheng 《International journal of quantum chemistry》2014,114(2):128-137
A series of halogen‐bonded complexes with diborane(4) 1 and its derivatives (Li 2 , methyl 3 , CN 4 ) as the halogen acceptors as well as with XCN, XCCH, XCF3, XF (X = Cl, Br, I) as the halogen donors have been investigated by means of quantum chemical calculations at the MP2/aug‐cc‐pVTZ level. The result shows that the B?B bond is a good electron donor in halogen bonding, particularly for the halogen donor XF. Interestingly, for the halogen donor XF, the halogen bond becomes stronger in order of IF < BrF < ClF. It is found that the addition of electron‐donating substituents greatly strengthens the halogen bonding interaction to the point where it exceeds that of the majority of H‐bonds. When the N atom in 2 ‐BrCN is combined with another interaction, its strength has a further increase due to the cooperative effect. This study combines the boron compounds with halogen bonds and would be significant for expanding their applied fields. © 2013 Wiley Periodicals, Inc. 相似文献
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研究了表面活性剂十二烷基苯磺酸钠(SLS) 存在时,meso 四( 对三甲胺基苯基) 卟啉[T(4 TMAP)P] 与铜的显色反应。在pH= 3 .7 的HAc NaAc 介质中,在SLS存在下,铜与[T(4 TMAP)P] 形成1∶2 的稳定配合物,至少在4 .5h 内吸光度无变化。最大吸收波长位于410nm ,ε= 3 .79 ×105L·mol- 1·cm - 1 。铜在0 ~1 .40μg/25mL内有良好线性关系。用于自来水及湖水中铜的测定,相对标准偏差小于3 % ,加标回收率在98 % ~103% 之间 相似文献
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Enantiospecific Synthesis of (R)‐3‐Amino‐4‐(2,4,5‐trifluorophenyl)butanoic Acid Using (S)‐Serine as a Chiral Pool
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Aytekin Köse Özlem Gündoğdu Derya Aktaş Meryem Fıstıkçı Ramazan Altundaş Hasan Seçen Yunus Kara 《Helvetica chimica acta》2015,98(2):260-266
Starting from (S)‐serine, a new method was developed for the synthesis of the β‐amino acid part of sitagliptin in ten steps and with an overall yield of 30%. The crucial step of the synthesis was the ring opening of N‐ and O‐protected (R)‐aziridin‐2‐methanol with (2,4,5‐trifluorophenyl)magnesium bromide to give N‐ and O‐protected (R)‐2‐amino‐3‐(2,4,5‐trifluorophenyl)propan‐1‐ol. 相似文献
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The crystal structure of [(p‐CH3C6H4)3GeCH(o‐CH3C6H4)CH2CO2]2Sn(C4H9)2 consists of a monomer with the atoms of tin and germanium both occupying tetrahedral geometries. However, the tin atom is distorted towards a skew trapezoidal bipyramid geometry as a result of weakly chelating carboxylate ligands. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献